Refuse collection vehicles that are employed to collect refuse (including recyclable materials) from collection containers are well-known. Such vehicles may include a container lifting assembly which engages and lifts a container into a dumping position over a collection compartment of the vehicle. The lifting assembly may be mounted on the front of the vehicle, on the rear of the vehicle or on the side of the vehicle. As used herein, the term “front of the vehicle” refers to the end of the vehicle where the cab is located and the term “rear of the vehicle” refers to the end of the vehicle opposite the front end. Refuse collection vehicles of this type generally include a packer ram that is used to push the refuse into an adjacent storage compartment and compact it, and which may also be used to eject the compacted refuse from the vehicle. The packer ram is generally located within the collection compartment or has a flat, angular or curved face assembly that forms a boundary wall of the collection compartment. A hydraulic cylinder or other force-applying mechanism is attached to the face assembly so that the face assembly may be extended to push the refuse into an adjacent storage compartment and compact it. In some cases, the face assembly may be further extended by the force-applying mechanism when desired to eject the compacted refuse from the vehicle. When fully retracted, however, the packer ram occupies some space on one end or side of or adjacent to the collection compartment. A removable or retractable top door is generally provided to cover the collection compartment and the components of the packer ram. However, when the top door is opened and the lifting assembly is engaged to lift a container into position for dumping (or when a container is otherwise lifted into position for dumping), it is possible for material from the container to fall onto the packer ram or in the collection compartment on the forward side (i.e. on the side away from or opposite the storage compartment) of the face assembly. Furthermore, when the packer ram is being extended to push the material into the storage compartment, some of such material may tend to ride up and over the packer ram to the forward side of the face assembly. Material that falls on the forward side of the face assembly may be difficult to remove and may interfere with the operation of the packer ram.
It is known to provide a shield to prevent refuse from falling onto the packer ram or in the collection compartment on the forward side of the face assembly. U.S. Pat. No. 3,170,377 of Herpich et al., U.S. Pat. No. 4,552,500 of Ghibaudo et al. and U.S. Pat. No. 4,648,775 of Verner all describe refuse collection vehicles of the type described above which include container lifting assemblies mounted on the front end and which are provided with such a shield. U.S. Pat. No. 3,211,309 of Shubin, U.S. Pat. No. 3,231,111 of Clar and U.S. Pat. Nos. 3,490,631 and 3,687,313, both of Smith, describe refuse collection vehicles having such a shield but no container lifting assembly. Instead of a front-mounted container lifting assembly, the vehicles of Shubin, Clar and Smith include a collection compartment that is accessible from the side of the vehicle.
The vehicle of U.S. Pat. No. 3,211,309 of Shubin includes a refuse collection compartment that has an opening in the bottom of a wall adjoining a refuse storage compartment through which a low-profile packer ram may be extended. The top of the packer ram cylinder is protected by a hinged cover that unfolds as the ram is pushed through the opening in the wall of the collection compartment into the storage compartment. U.S. Pat. No. 3,231,111 of Clar describes a vehicle having a packer ram assembly that is similar to that of Shubin. The collection compartment and adjacent storage compartment of the Clar vehicle are separated by a wall or partition having an opening at the bottom for the packer ram. The packer ram assembly includes a cylinder and a linkage system that is protected from intrusion of refuse within the collection compartment by a shield plate that is pivotally mounted at one end to one of the links of the linkage and arranged so that the free end slides across the top wall of the packer face assembly as the packer face is extended. U.S. Pat. No. 3,490,631 of Smith describes a refuse collecting vehicle that is similar to those of Shubin and Clar. A flexible cover is attached at one end to the packer ram of this vehicle for preventing refuse from dropping behind the packer ram as it is extended to push the refuse into an opening in the wall separating the collection compartment from the storage compartment. The other end of the flexible cover is attached by a spring-loaded system to the wall of the collection compartment opposite the storage compartment wall. U.S. Pat. No. 3,687,313, also of Smith, describes a shield for a refuse vehicle collection compartment that is similar to that described in U.S. Pat. No. 3,490,631. This shield is comprised of a flexible curtain that extends over a transversely-disposed, spring-loaded roller and is attached to a frame member within the wall of the collection compartment opposite the storage compartment wall. Another embodiment of the invention of Smith's '631 patent includes a sloping shield that slides across the top of the packer ram face assembly as the ram face plate is extended to push refuse into the storage compartment. U.S. Pat. No. 4,552,500 of Ghibaudo, et al. describes a refuse collection vehicle that may include a front-mounted container lifting assembly, or the container lifting assembly may be deleted to provide a collection compartment into which refuse may be loaded by hand from the side. The front-loading embodiment of the Ghibaudo vehicle includes a packer ram having an extended top plate which is contained within a canopy over the cab when the ram is fully retracted. The top plate is long enough to extend beneath the opening in the top of the collection compartment when the ram is extended to push refuse into the storage compartment. U.S. Pat. No. 4,648,775 of Verner describes a front-loading refuse collection vehicle which includes a packer ram having a face assembly which includes a shield plate that is hingedly attached to the upper portion of the ram. The other end of the shield plate is provided with shoes that slide within a guide channel on either side of the collection compartment.
All of these prior devices include one or more disadvantages. For example, the shield panels of Shubin, Clar and Smith (both versions) are adaptable, because of height restrictions, only to vehicles provided with a wall between the collection compartment and the storage compartment having an opening in the lower portion thereof for passage of a low-profile packer ram. The shield plate of Ghibaudo is a large heavy object which requires that the vehicle be provided with an equally large over-the-cab canopy. In addition, since the Verner shield plate is attached to and extends upwardly from the top of the packer ram in the compaction zone of the vehicle, it essentially forms the top portion of the packer face and would be subject to at least a portion of the resistance forces imposed by the refuse being packed into the storage compartment. The imposition of such forces would require, therefore, that the Verner shield possess the requisite strength and rigidity to overcome them. In addition, the guide channels of the Verner shield assembly extend nearly the full length of the collection compartment, which offers significant opportunities for refuse to be retained therein as refuse is dumped into the collection compartment and the packer ram is extended therethrough. Any such refuse that may become lodged in either or both of the guide channels may interfere with the operation of the shield or the packer ram.
It would be desirable if a packer shield could be developed for a refuse collection vehicle that would avoid the disadvantages of the previously-known devices.